The experiment has already dipped into some North American venues where the virtual likeness of deceased crooner Roy Orbison received mixed reviews a few months ago. Opera singer Maria Callas was also resurrected in a performance some critics say looked more like she was a floating ghost than a physical entity. Glenn Gould will be added to the hologram circuit in 2019, with the late Canadian pianist accompanied by live orchestras as part of a tour organized in co-operation with his estate. – Toronto Star